The invention relates to a housing flange unit and to a use of the housing flange unit.
Housing flange units are known. They generally have gases flowing through them and are of multi-part construction. They generally have a butterfly valve shaft which is mounted rotatably perpendicularly with respect to the longitudinal axis of the housing flange and on which a butterfly valve for closing pipeline units is arranged. In this case, it is generally desirable that the gases cannot pass into the open air via the bearings of the butterfly valve shaft, particularly if the gases contain harmful substances. This possibility is provided by the fact that the butterfly valve shaft is generally driven externally and, as a consequence of high temperatures to which the housing flange unit is generally exposed, appropriate sealing by means of sealing rings cannot be effectively realized.